~

1. PHOTOELECT
RIC
EFFECT
Nabilah Ashriyah XII-C

2. DEFINITION
 The photoelectric effect was first observed in 1887 by Heinrich Hertz
 Photoelectric Effect (photoemission) is the emission of electrons
from a metal surface due to electromagnetic radiation (by light)
 Photoelectrons are the emitted electrons

3. Where;
 E = energy of the absorbed photons (J)
 f = frequency of absorbed photons (Hz)
 h = Planck’s Constant (6.625 x10-34 Js)
 c = speed of light (3 x108 m/s)
 λ = wave length (m)
 ϕ = minimum energy to remove one e-
 Ek= kinetic energy of a photoelectron
1 eV = 1.6 x10-19 J
hc = 12400 eVÅ
FO RMU L A

4. EXCERCISE
UV radiation having a wavelength of 120 nm falls on gold metal, to which electrons
are bound by 4.82 eV. What is the maximum kinetic energy of the ejected
photoelectrons?
Solution